Multiple blast aerator system

Abstract

A multiple blast aerator hopper system for handling bulk material. A plurality of blast aerators are fitted at radially spaced-apart intervals about the periphery of the hopper; the first blast aerator is positioned near the bin outlet, and each succeeding aerator is usually vertically elevated thereabove. The blast aerators are periodically fired in a timed, rotary sequence starting with the first, lowermost aerator and continuing serially with higher, radially spaced-apart aerators. Preferably each aerator includes an internal valve seat assembly which houses a resilient, dual diameter piston for axial movement between the sealing position and a rearward, aerator fill position. An external solenoid valve controls each aerator. Preferably the blast discharges of each aerator are directed downwardly, tangentially with respect to the walls of the bin or hopper on which the system is mounted.

What is claimed is: 
     
       1. A multiple blast aerator hopper system comprising: a generally upright, rigid storage bin having walls, an outlet and an inlet;   a plurality of blast aerators mounted on said bin at radially spaced-apart intervals about the periphery thereof, each aerator comprising: a generally cylindrical, rigid tank having an axis, and a front end fitted with a blast discharge opening coaxially aligned with respect to said axis;   a rigid, elongated, tubular, blast discharge pipe adapted to be coaxially secured and aligned within said tank, said pipe having a front output end, a rear end positioned interiorly of said tank, a counter-bored, internal front shoulder seat, and a predetermined intermediate internal diameter;   a piston seat assembly coaxially positioned within said blast discharge pipe in abutting relation with respect to said internal shoulder, said seat assembly including a rear, chamfered seat;   a resilient, generally cylindrical, dual diameter piston coaxially disposed within said blast discharge pipe and axially displaceable between an aerator tank fill position and an aerator tank exhaust position; a main body portion of said piston having a diameter substantially equal to said blast output pipe predetermined intermediate diameter and a front portion of said piston having a diameter less than said discharge pipe intermediate diameter and terminating in a front, chamfered portion adapted to matingly engage said piston seat assembly chamfered seat when said piston assumes said aerator fill position;   vent means defined in said blast discharge pipe for outputting air temporarily stored within said tank through said blast discharge pipe front output end in response to movement of said piston to said aerator tank exhaust position;   end cap means adapted to be coaxially, sealingly coupled to said blast discharge pipe rear end for limiting rearward axial displacement of said piston, the end cap means operable to define a sealed cavity between it and said piston at the rear of said blast discharge pipe; and,   valve control means in fluid flow communication with said cavity for filling said cavity and thus said tank and for subsequently initiating an output blast by venting said cavity;     the first of said blast aerators mounted closest to said storage bin outlet, and each successive blast aerator being mounted higher than the previous blast aerator; and,   timing means for initiating a timed sequence of air blasts by firing said blast aerators in a predetermined operational sequence.   
     
     
       2. The system as defined in claim 1 wherein each piston includes a shoulder defined between said main body portion thereof and said reduced diameter portion thereof, said shoulder forming a working surface against which tank pressure may urge said piston toward said rear end of said blast discharge pipe in response to venting of said cavity. 
     
     
       3. The system as defined in claim 2 wherein each valve control means comprises: first air injection fitting means coupled to said end cap means for injecting air into said cavity rearwardly of said piston whereby to pressurize said cavity and move said piston into sealing engagement with said chamfered seat;   check valve means coupled to said end cap in fluid flow communication with said cavity for pressurizing the interior of said tank in response to pressurization of said cavity; and,   solenoid valve means for first actuating said air injection fitting means whereby to fill said tank through said check valve means and then depressurizing said cavity at a preselected time whereby to suddenly exhaust said tank through said output pipe in response to resultant rearward displacement of said dual diameter piston.   
     
     
       4. The system as defined in claim 3 wherein each solenoid valve means is located exteriorly of said tank. 
     
     
       5. The system as defined in claim 4 wherein said timing means fires said first blast aerator first, and then successively fires the next higher blast aerator until a blast cycle is completed. 
     
     
       6. The system as defined in claim 5 including means for varying the time between successive firing of aerators. 
     
     
       7. The system as defined in claim 6 wherein each of the blast discharge pipes enters the storage bin at a downward, tangential angle with respect to said walls.